Abstract: Several theories of cognitive control or executive function (EF) propose that EF development corresponds to children's ability to form and reflect on represented stimuli in the environment. However, research on early EF is primarily conducted with preschoolers, despite the fact that important developments in representation (e.g., language, gesture) occur within the first years of life within a social context (e.g., to share, communicate, and collaborate, see Tomasello, Carpenter, Call, Behne, & Moll, 2005). In the current study, children's EF performance and the relationship between EF and early representation (i.e., joint attention, language) were longitudinally examined in 47 children at 14 and 18 months of age. Results provided support for a unidirectional relationship in which earlier joint attention behavior at 14 months was related to better EF at 18 months. Specifically, higher level initiation of joint attention behaviors at 14 months (e.g., pointing to manipulate another's attention) were related to stronger, more cohesive EF performance at 18 months. Children's performance on EF tasks was low at 14 months and improved from 14 to 18 months. Although EF performance during this period revealed patterns dissimilar to later EF development in preschool (e.g., low inter-task correlations, few significant relations to language), by 18 months of age a subset of children consistently passed the majority of EF tasks, possibly indicating the emergence of a unified EF in the second year of life. These results provide evidence that preverbal means of representation (i.e., initiation of joint attention) are related to early EF (e.g., Zelazo, 2004). Further, early representation that emerges within a social context (e.g., to communicate information to another person) may underlie the emergence of a unified EF ability, as only children demonstrating higher-level initiation of joint attention behaviors were able to guide behavior across multiple EF contexts.